Doton on Bosses, am i missing something?

[Shurrikhan]

Doesn't Doton do more than Raiton with Kassatsu, because Kassatsu makes all the ticks of the DoT crit?

All-crit 360 is still less than all-crit (because there's only one hit) 400.

Though, Kassatsu doesn't cause auto-crit now, anyways, just increased damage. (The effect on all ticks still applies.)